Macintosh PowerBook Duo 280 and 280c systems use a Motorola 68LC040 microprocessor which does not have an integrated math coprocessor, otherwise known as a floating point unit (FPU). Some software packages may require an FPU and therefore will not run on this series of computers.
In addition, the 68882 math coprocessor option for the Duo Dock and the built-in FPU of the Duo Dock II are not compatible with the 68LC040 used in the Duo 280 and 280c systems. These computers will still operate in the Duo Dock, but will ignore the installed 68882 math coprocessor.
Users with software packages that require an FPU should contact the software vendor for assistance.